Latching mechanism



od. s, 1945.

H. n. CAHILL LATCHING HEGHANISH Filedsept. 22, 1944 2 Sheets-Shee'f 2 /NVENTOR HD. CAH/Ll.

Arron/wwl Patented Oct. 8, 1946 UNITED STATES PATENT OFFICE LATCHING MECHNISM Harold D. Cahill, Scarsdal'eg; N.l assigner tov Belll Telephone Laboratories;Incorporated, New York, N. Y., a corporation ofy New York Application September 22, 1944;'S-erial No; 555,358

ThisI invention' relates tdapparatus mountings and-particularlyto latching means for releasably locking an apparatuslunit in position on a mounting frame. l

It is the object of this invention to simplify it is-thepractice to provideduplicate plug l.boards sov that' the. anticipatedv circuit changes may be made/,on one board' while thefother board is in,

service;A Whenf therequired'chan'gesare made, :the `plug board in service is removed iromitsmounting and the previously prepared-board substitutedl therefor.V Thislpractice permits` -thevsubstitution of a completelyr differenti set vof'fcircuit interconnections for'- al set previously iin. service', withusubstantiallylno delay. YSuchplug!l boards arer usually mountedbetween the vertical members of' a switch mounting frame; andi arev accessible from the fronti off the frame forwithdra-wal therefrom. f j

In accordancel with a feature ofthe present invention, asimplied latching" mechanism is'l provided which functionsautomatically,'upon the insertion of` the plug boardinto themounting frame, to lock the board initshome4 position, and to'dofso'in suchl a manner'aslto eliminate sub!- stantially'all relative play betweenftheboard and the .mounting fra-me;

Anothergfeature of the invention resides in'an latch mechanism which, when' manually oper-- atedto its unlatching position, functions'vautomaticaliyY to partially' eject the 'boardf from"vr its'- homeposition andV tothereby preclude the possibility of -they latchl resuming its'latching position when the hands' of fthe-1' person` engagedl inv withdrawing the board from theiframe 'are transferredifrom the latch releasingf members totheboard `for electing;v the;` removal" of thel board.. This Lfeaturef is -particularl7 desirable 'where the plug" board -i's'foff such sizeA and weight as tore 10 Claims. (CL. 248-661)` 2 quire the-use of both' hands in its removal since, once the latch is manually operated to its unlat'ching position, it requires no further attentionandv leaves both hands ifree to perform the actual removal operation.

These andA otherv features of the invention'w-ill bei readilyunderstood from the following detailed description when read in connection with'l the accompanyingldrawings, in which:

Fig. 1 is a perspectiveL View of a plug board to which the latchingmechanism of this invention is particularly adaptable and shows one ofthe en'd plates thereof removedso as to expose the interior "of the plug boar-d;

Fig. 2 isi an end view' of the' plug board with the fendi plate removed, 'and illustrates the manner in which? theinterior.'terminals of the board are electrically interconnected; A

Eig.: 31v isa p'erspective View of av latch-supportingm'ounting tray fixed to a, pair of vertical channelfmembersof a mounting frame, and the plug board inI` removed aligned relation thereto; and

Figs. 4,:5and6 show-threev views of the latching mechanism. In Fig Llftlfiel'atch is shown in itsalat'ching position.; in Fig; 5" it is shown' in the positioneitoccupies just prior to reaching its unlatchir'igfposition when vmanually operated; and infFig.z 6^it isrshown 'after it has functioned to unlatchljt'hezplug/board and to partially eject the same: 1

Th'efplugf board' consistses'sentially of an elongatedirect'angulai` front panel Ill-of. suitable insulatingimaterial anda; metallic frame I2 which, with the front panel Ill and two en'd plates I3,y servesto'effect an enclosure fortheinternal wiringflof'ethefb'oard A pair of angle members I4 of Figs: 1 andZby'then'umeral |52 and provide `sufcient clearanceto permit. the'frame' I2" to be secureditotheangle members I4 vby any suitable meansrsuch'z as screws a (not shown) The panel I0 accommodates-'six rows effe-'1 male; orjack 'type contacts- IIf each' of which `is provided latit,V` inner end with a terminal lug I 'I2 In'thef panelillustrated; each row of jack contacts i's iintendd ltol include" forty'A contacts maki totaloi"twofhundred and forty such jacks; 'Iliese-ja'cks protrudethrough the panel so as into irenderf themy accessible'v from the* front 1D for the accommodation of plug-ended cords, such as shown at i8 in Figs. l and 2, by means of which interconnections between any pair of jacks I may be made.

The frame I2 is formed so as to effect two substantially rectangular portions, one having its longer dimension slightly greater than the height of the panel Ii), and the other having its longer dimension slightly greater than the height of the jack-type terminal units I9 which are fixed to the inner face of the rear wall of the frame I2 by means of small angular brackets 20, there being two such brackets fixed to each side of a terminal unit I9 and secured to the rear wall of the frame I2 by screws, as illustrated. The rear wall of the frame I2 is provided with a series of equi-spaced apertures, or windows through which the female contacts of the terminal units I9 are accessible for the reception of corresponding multiplug contact units not shown. As shown in Fig. 2, each jack-type multicontact unit I9 is provided with a plurality of terminals 2| which may be individually connected to the individual terminals I1 of the jacks I6 carried by the panel Iii, by wires such as shown at 22 in Fig. 2. Obviously, the connections of the wires 22 to the terminals I1 and 2l may be made in any suitable manner.

Above each row of jacks on the front face of the panel I0 is located a designation strip 24 for the purpose of providing means for identifying the circuits associated with the jacks.

Each end plate, at its lower edge, is provided with an integral flange 60. The flanges of the end plates I3 project inwardly and provide seats upon which a shelf 3! is adapted to rest and to be secured thereto by means of screw bolts 62 and nuts 33, one set of which is shown in Fig, 1. The shelf I, at its forward end terminates'in a rolled portion constituting a hand grip 26 which facilitates the withdrawal an'd removal of the board from its support on the mounting frame. The leads of the plug ended cords I3 rest upon the shelf 3 I as shown in Fig.l.

At suitable points near each end of the frame I2 are fixed four angle brackets 21 to which are secured the end plates I3. As shown in Fig 1, four screws 28 are screwed into suitably threaded holes 29 in the end plates and pass through corresponding holes in the angle brackets 21 to receive the nuts 30. Thus, when the end plates are placed inV position and held therein by the screws 28 and the nuts 3U, the interior of the plug board is completely enclosed.

On the outer surface of each end plate I3 and fixed thereto is a horizontal steel bar or runner 32, which, as will be described presently, is adapted to ride upon a slide rail 33 fixed to the inner surface of each of the side walls of the tray 34.

At 3'5 in Fig. 3 there are indicated portions of the vertical channel members of a switch mounting frame. An angle bracket 36 is adjustably mounted on each channel 35 as illustrated. The side walls of the tray 34 are fixed in any suitable manner to the brackets 36. The tray thus constitutes a compartment into and out of which the plug board may be slid.

Each side wall of the tray 34 supports, on its inner face, a latching unit and the slide rail 33, the latter, in each case, being located immediately l below the latching unit, Each latching unit comprises a manually operable latching lever 40 pivotally mounted on a small rectangular plate 4I by means of a pivot screw 42. Thelever ,40at its lower edge and substantially midway of its length, is provided with a depending lug or tooth 43. A small L-shaped lever or bell crank 44 is disposed immediately above the lever 40 and to the rear thereof, being pivotally mounted at its elbow to a small plate adjustably xed to the inner face of the side wall of the tray. On its upper edge, the lever '44 carries two springs 46 and 41 in superposed contiguous relation. These springs are ixed to the lever 44 in any suitable manner so as to project forwardly from the forward end of the horizontal arm thereof. The lower spring 41 is inclined in the direction of the lever 4G so as to be engagea-bly associated therewith.

Normally, that is when the plug board is removed from the mounting frame, the lever 4U would assume a position such that the integral lug 43 thereof would rest upon the slide rail 33. Thisposition of the lever is not shown in Fig. 3 since this gure is intended to show the lever position when the plug board is positioned on the mounting frame. Since, to show the plug board in this position would obscure the latching mechanism, the board is illustrated removed from the frame.

When the plug board is inserted bodily in the mounting frame the rear edges of the supports or runners 32 ride up on the forward inclined ends of the slide rails 33, and as the board is pushed to its home position the levers 40 are raised to positions similar to that shown in Fig. 6, until the lugs 43 thereof clear the forward ends of the corresponding supports 32 fixed to the exterior of the side plates I3 of the board. The levers 49, under the action oi.v their associated springs 4% and 41 and by the force of gravity, assume their latching positionssuch as illustrated in Figli. lt will be observed that when the plug board is inits home position the rear ends of the supports 32 abut the depending legs of their corresponding levers or-bell cranks 44 so that the springs 41 are tensioned against their corresponding levers 40 thereby firmly maintaining the levers 40 in their latching positions and precluding any shifting of theV plug board in a horizontal direction.

To initiate the removal of the plug board from the mounting frame the forward upturned ends of levers 40 are manually lifted, one lever being manipulated by each hand of the person removingl the board. As the levers 43 are raised, the springs 41 are put under tension and as the levers approach the stop 50 this tension is augmented by the tension of springs 46, it being understood that the depending legs of the levers 44 abut the rear ends of the supports 32 during the upward movement'of the levers 40. Thus, a considerable tension is built up in the springs 45 and 41 until the lugs 43 of the levers 4U clear the forward ends of the supports 32, at which time,when the board is noY longer restrained from moving forwardly by the engagement of the lever lugs 43 with the forward-ends of the supportsv32, the energy stored in the springs 46 and 41 is utilized invcausing the levers 44 to v40,1eahes Stop ,5.0 and exert additional; vpressure on. inmersa?,- .It will li-,notes than when une hands are, rernved,` from the'lerers 41li-arid the. plus, beer'dis energetically ejected frmitshome position, the levers llllnare heldin raisedpositions by virtue ofthe lugs 4.341r thereof riding on the upper surface of the runners l32. vllll'ithout the initial automatic-ejection feature it is apparent that the levers when raised to vtheir unlatching positions would have to, somehow, be held in such positions until the board was manually withdrawn from its home position u ntil the lever lugs d3 were cleared by the front end' ofthe runners,

therefrom. Both hands may then b e employed in withdrawing the plug board from the lmounting frame. 7 d' What is claimed is:

l. In combination, an apparatus mounting tray, an apparatus unit having a home position on said tray, a manually operable latch for locking said unit in its home position in said tray, and. means coupled to and controlled by said latch whcn manually operated to an unlatching position for ejecting said unit from its home position on said tray.

2. In combination, a` stationary tray, an apparatus unit movable into 'said tray so as to occupy a home position thereon, side wall projections on said unit, manually operable latches on said tray each cooperating with a different one of the side wall projections on said unit for locking said unit in its home position on said tray, and means controlled by said latches when manually operated to unlatching positions for ejecting said unit from its home position on said tray.

is, inserted in said mounting frame Yfor locking.

ablelatch operable automatioally.V when. said unit said unit in its. homefposition in said frame, and means` operable by s aid latch when said latch is manually operated toi an unlatching position for automatically ejecting said unit from its home position in saidxframe.

5,. In combination, a receptacle having sideV walls to each of which is Xed a slide rail, an apparatus unit having end wallsv to 'each of which is fixed a runner, the runners of said unit being slidable on said slide rails when said unit is.

inserted into said receptacle,` a' manually perable latchingr lever pivotally rmounted on each side wall of said receptacle for engagement with corresponding runners of said unit when saidr unit is inserted in said receptacle so 'as to occupy a home position' therein, whereby said unit' is locked in the said home position,and means'controlled by said latching leversand rendered cliccrec'eptacle.

6,. In combination, an apparatus unit, a pair Y v of spaced frame members, a'support for said unit 3. In combination, a stationary trayhaving e side walls, an apparatus unit movable into said tray so as to occupy a home position thereon, end wall runners mounted on said unit having front and rear ends, a latch lever pivotally mounted on each side wall of said tray, a bell crank for each lever pivotally mounted at its elbow on the corresponding side wall of said tray and having one leg thereof in spaced superposed relation to its corresponding lever and with its longitudinal axis parallel to the longitudinal axis oi' said lever and a second leg disposed to the rear of said lever and with its longitudinal axis at right angles to the longitudinal axis of said lever, and biasing springs supported on said one leg of each of said bell cranks and extending therefrom in cooperable engagement with the corresponding lever, said second leg of each of said bell cranks being engageable by the rear ends of said end wall runners of said unit when said unit is moved into its home position on said tray to cause said biasing springsl to force said levers into latching engagement with the forward ends of the said end Wall runners and said springs being operable to cause the said second leg of each of said bell cranks to act upon the rear ends of said end wall runners when said levers are manually operated to `their unlatching positions to eject said unit from its home position on said tray.

4. In combination, a mounting frame, an apparatus unit, a latching mechanism supported by said mounting frame including a manually opercomprising a pair of slide rails eachv ilxed to a adapted to slideA on said slide vrails whenl said. unit is inserted between said frame members, a pair of manually operable; latch levers' each cooper' ating with. one of said runners when said Vunit slid on said railsl so rasto occupy ahome position between said members for locking said unit in the said home position, and means responsive to the manual operation of said latch members to unlocking positions for automatically dislodging said unit from its home position between said frame members.

7. In combination, an apparatus unit having side walls, a runner lixed exteriorly to each side wall of said unit, a receptacle for housing said unit comprising a pair of spaced frame members and a tray having oppositely disposed side walls fixed each to one of said frame members, a slide rail fixed to the interior face of each of the side walls of said tray and adapted to accommodate the runners of said unit when said unit is inserted in said receptacle and to permit relative sliding movement therebetween, a manually operable lever pivotally mounted on each side wall of said tray in superposed relation to the corresponding slide rail for effecting a latching engagement with one of said runners when said unit occupies a home position on said rails, spring tensioning means for biasing said levers in their' latching positions and for storing energy when said levers are manually operated to their unlatching positions, and means eifective when said levers reach their unlatching positions for utilizing the energy stored in said spring tensioning means to dislodge said unit from its home position within said receptacle.

8. In combination, an apparatus unit of appreciable size having end walls, a runner xed to the exterior of each end wall of said unit, a mounting frame comprising a pair of spaced frame members, a tray having oppositely disposed end walls each fixed toV one of said frame members to define a compartment for the accommodation of said unit, a slide rail iixed to each end wall of said tray upon which the runners of said unit slide when said unit is inserted in the compartment dened by said tray, a latching mechanism mounted on each Wall of said tray in superposed relation to the corresponding slide rail and each comprising a manually operable pivotally mounted latching lever having an integrally formed detent engaging the forward end of a corresponding one of said runners when said unit is inserted in said compartment so as to occupy its home position therein, and means engageable with the rear ends of said runners and controlled by said latch levers when said latch levers are manually operated to unlatching positions for ejecting said unit from its home position.

9. In combination, a supporting structure comprising two spaced frame members, a tray having side Walls fixed to said frame members and each Wall supporting a horizontally disposed slide rail, a plug board having rigidly fixed to each end thereof a runner adapted to slide on a corresponding slide rail when said plug board is moved into said tray, means for latching said plug board to said tray when moved thereinto so as to occupy its home position comprising a latch lever pivotally mounted on each side Wall of said tray in superposed relation to the slide rails so as to permit the free passage of each of said runners between a latch lever and slide rail as the plug board is moved on said slide rails into its home position, a detent integrally formed on each of said levers, spring biasing means effective when said plug board reaches its home position in said tray for biasing said levers in their latching positions'in which the integrally formed detents thereof each abut one of the ends of corresponding ones of said runners so as to maintain said plug board in its home position, and means comprising a pair of bell cranks each carrying at one end said spring biasing means and having its other end abutting the other end of a corresponding one of said runners, responsive to the manual operation of said levers to their unlatching positions for ejecting said plug board from its home position.

10, A latching mechanism for releasably locking a plug board in a stationary tray having slide rails upon which runners xed to the ends walls of said plug board are adapted to slide in either direction as the plug board is moved into and out of said tray, comprising a pair of manually operable latching levers, a bell crank for each lever, and spring tensioning means xed to each of said bell cranks and engageably associated with a corresponding lever, said levers and bell cranks being independently pivotally mounted on said tray and so disposed relative to one another and to the slide rails of said tray that, when the runners of said plug board are moved in one direction on the slide rails of said tray as the plug board is moved to its home position in the tray said bell cranks are engaged by said runners to cause said spring tensioning means to bias said latches in locking engagement with said runners to lock said plug board in its home position in said tray, and when said latches are manually operated to their unlatching positions said spring tensioning means causes said bell cranks to move said runners in the other direction on said slide rails and to thereby eject said plug board from its home position in said tray.

HAROLD D. CAHILL. 

